Photoelectric detonator using two photoelectric cells



Nov. 10, 1936. J. H. HAMMOND. JR 2,060,201

PHOTOELECTRIC DETONATOR USING TWO-PHOTOELECTRIG CELLS Filed Jan. 5, 19342 Sheets-Sheet l NOV. 10, 1936. J HAMMOND, JR 2,060,201

PHOTOELEGTRIC DETONATOR USING TWO-PHOTOELECTRIC CELLS Filed Jan. 5, 19342 Sheets-Sheet 2 Patented Nov. 10, 1936 UNITED STATES PHOTOELECTRICDETONATOR- USING TWO PHOTOELECTRIC CELLS John Hays Hammond, Jr.,Gloucester, Mass. Application January 5, 1934, Serial No. 705,357

13 Claims.

The invention relates to ordnance devices and more particularly totorpedoes.

According to one form of the invention, a torpedo maybe provided withlight sensitive devices which control the detonation of the explosivecharge thereof when it passes beneath a ship. The torpedo mechanism mayinclude a plurality of photoelectric cells which are energized by thelight of day transmitted through the water above the torpedo. When thetorpedo passes beneath a ship, the shadow causes the deenergization ofthe photoelectric cells which in turn may be arranged to cause thedetonation of the war head of the torpedo. Some of the photoelectriccells may be arranged to receive light from directions different fromothers to compensate for variations due to the rolling of the torpedo.

The invention may also provide a means whereby the detonation of the warhead of the torpedo is delayed a predetermined time after the photo.-sensitive means has passed into the shadow of the ship in order to allowthe explosion to occur near the central portion of the vessel, where itwould be most effective, rather than at the so called blister" where itwould be comparatively in-,

effective.

The invention also consists in certain new and original features ofconstruction and combinations of parts hereinafter set forth andclaimed.

Although the novel features which are believed to be characteristic ofthis invention will be particularly pointed out in the claims appendedhereto, the invention itself, as to its objects and advantages, the modeof its operation and the manner of its organization may be betterunderstood by referring to the following description taken in connectionwith the accompanying drawings forming a part thereof, in which Fig. 1represents diagrammatically the forward portion of a torpedo providedwith this invention as seen from below,

Fig. 2 is a section taken on line 2--2 of Fig. 1,

Fig. 3 is a section similar to Figure 2 of a modified form of theinvention, and

Fig. 4 diagrammatically illustrates a modified form of circuits used inconnection with this invention.

Lke reference characters denote like parts in the several figures of thedrawings.

In the following description and in the claims, parts will be identifiedby specific names for convenience. but they are intended to be asgeneric. in their application to similar parts as the art will permit.

Referring to the accompanying drawings, and

more particularly to Figures 1 and 2, there is shown a water-borne bodysuch as a carrier of explosives having a water tight torpedo hull l0,and arranged to be propelled in the usual manner by propellers locatedat the after end. The hull 5 I0 is provided with two transversebulkheads II and I2, thus providing two compartments l3 and I4, theformer being filled with an explosive charge l5, such for example asTNT.

Two holes are provided in the hull III in the upper part of thecompartment l4. Each hole is covered by a sheet of glass or othertransparent material. Mounted in two tubes I1 and I8 are two lenses l3and 23 which are positioned in line with the corresponding holes in thehull. 5 The interiors of the tubes are painted a flat black so as not toreflect any light. Positioned at the foci of the lenses l9 and are twophotoelectric cells 2| and 22 which are connected in parallel to theinput circuit of an amplifier 23. 20

A clock-work mechanism 25 is provided which drives a commutator 26. Thiscommutator is provided with a conducting segment 21. To the shaft of thecommutator is secured an arm 28 which normally engages a pin 29. Asecond pin 25 30 is provided for limiting the motion of the arm 23 andthe commutator 26.

For automatically starting the clock-work mechanism 25, a heavy weight3| is secured to the end of a fiat spring 32, the upper end of which is30 fastened to the casing of the clock-work mechanism 25. The weight 3|is provided with a projection 33 which normally engages a finger 34which controls the starting of the clock-work mechanism. Engaging theend of the finger 34 35 is a spring 35 which is supported on a bracket36.

Engaging the commutator 26 are four brushes 38, 33, and 4|. The brush 38is connected to one side of the output circuit of the amplifier 23. Thebrush 39 is connected to one side of a solenoid 42, the other side ofwhich is connected to the amplifier 23.

The solenoid 42 is provided with a core 46 which is adapted to be movedto the left as shown in Fig. 1 when this solenoid is energized. Secured5 to one end of this core is a piston 41 which reciprocates in acylinder 43. This cylinder is provided with a port 49 covered by a flapvalve 50 which is adapted to allow air to escape rapidly from thiscylinder. The cylinder is also provided 50 with a port 5| the opening inwhich is controlled by a needle valve 52 for restricting the fiow of airthrough this port.

To the other end of the core 46 is secured an insulating member 55between which and the 55 2 solenoid 42 is mounted a compression spring56. Mounted on the insulating member 55 is a contact 51 which isconnected to the contact 4| and at suitable times engages a conductingsegment 58 mounted on an insulating base 59. The segment 58 is connectedto one side of a detonator t8, the other side of which is connected tothe contact 40 through a battery 6|.

In the operation of this. system when the torpedo is fired the inertiaof the weight 3| causes it to be moved backwardly relative to thetorpedo, thus disengaging the projection '33 from the figure 34 which ismoved upwardly under the action of the spring 35, thus causing theclockwork mechanism to start turning the commutator 26 at apredetermined speed. After a predetermined interval of time the segment21 0f the commutator 26 will engage the brushes 38 and 39, thusconnecting the amplifier 23 to the solenoid 42 which will be energizedas the photoelectric cells 2| and 22 will by this time be receiving thelight of day focused upon them by means of the lenses l9 and 20.

This will cause the core 46 of the solenoid 42 to be moved rapidly tothe left as the air in the cylinder 48 is freely exhausted through theport 49. This condition continues as long as the photoelectric cells 2|and 22 receive light through the lenses I9 and 29. I

When the torpedo passes beneath an enemy ship, the light be cut off fromthe photoelectric cells 2| and 22 thus causing the deenergization of thesolenoid 42, which allows the core 46 to be moved slowly to the rightunder the action of the spring 56, the speed of this motion beingdetermined by the setting of the needle valve 52. After a predeterminedinterval of time the contact 51 will engage the segment 58, thus closingthe circuit from the battery 6| through the segment 2'! and contact 51to the detonator 68 which is detonated, thereby exploding the charge ofexplosive iii in the war head of the torpedo.

This explosion will take place directly under the center of the ship asthe mechanism has been so timed that it will give the torpedo asufilcient length of time to reach this position.

By the use of two photoelectric cells connected in parallel and locatedwith their optical axes at on either side of the vertical, it'ispossible to compensate for any rolling of the torpedo which "otherwisewould affect the light received by a single photoelectric cell.

In order to. prevent the premature explosion of the torpedo in the eventthat it should pass under some floating debris and thereby momentarilyoccult thelight sensitive means, any type of well known delay actioncircuit may be incorporated in the amplifier 23, so as to make itnecessary for the photoelectric cells 2| and 22 to be occulted for anappreciable-length of time before the operation of the mechanism willbeinitiated. An important advantage of this system of running torpedoesat considerably greater depths than are now used is the fact that atthese depths the wakes are much farther behind the torpedoes when theycome to the surface due to the longer time it takes the bubbles of airto rise to the surface and that the wakes are much less conspicuous dueto the fact that the air has had a longer time to become diffused in thewater. It is, therefore, much more diilicultto observe and locate thesetorpedoes than those run at'present-day depths.

In themodified form of the invention shown in Fig. 3, a singlephotoelectric cell 65 is used in place of the two cells 2| and 22 and islocated at the focus of the lenses i9 and 20. This photoelectric cell isconnected to the input circuit of the amplifier 23. The system functionssubstantially the same as that shown and described in 5 connection withFigures 1 and 2. In this case if the torpedo should roll the lightreceived by the cell 65 will remain practically constant due to the factthat the light transmitted through one lens will increase in proportionas the light in the other lens decreases.

In the modified form of the invention shown in Fig. 4 two photoelectriccells 68 and 59 take the place of the photoelectric cells 2| and 22.These cells are of the new type similar to those developed by the WestonInstrument Company and by the Westinghouse Electric ManufacturingCompany. These cells do not require the use of the amplifier butgenerate sufiicient current so that they will, operate a sensitive relaydirectly and are shown in this figure as connected to the winding of asensitive relay 18. This relay controls the circuit through a battery IIand a solenoid 12. The core 13 of this solenoid is provided at itsdistal end with a piston 14 which reciprocates in a cylinder 15. Thiscylinder is provided with a port 16 covered by a flap valve II which isadapted to allow air to escape freely from this cylinder. The cylinderis also provided with a port 18 the opening in which is controlled by aneedle valve I9 for restricting the flow of air through this port.

To the central portion of thecore I3 is secured an insulating member 8|between which and the solenoid 12 is a compression spring 82. Carried bythe insulating member 8! is a contact 83 which is connected to the brush38 of the clock-work mechanism 25 shown in Fig. 1. At suitable times thecontact 83 engages a stationary contact 84 which is connected through abattery to the winding of the solenoid 42, the other side of the windingof which is connected to the brush 39 of the clock-work mechanism 25.

In the operation of the modified form of the invention shown in Fig. 4,the photoelectric cells 68 and 69 are energized by light focused uponthem by the lenses l9 and 20 causing the operation of relay III whichcloses the energizing circult of solenoid 12, thus causing its core 13to be moved to the right against the action of the spring 82. This willcause the movable contact paring an energizing circuit for the solenoid42 'through commutator brushes 38 and 39 as already described inconnection with Fig. 1. Solenoid 42 will be energized and its core movedto the left when brushes 38 and 39 are engaged by commutator segment 21,as previously described.

In case the torpedo should pass under floating debris or other materialwhich would momentarily out oil the supply of light, the relay III willbe opened, thus deenergizing the solenoid 12 which will allow the core13 to move slowly to the left under the action of the spring 82, thespeed being determined by the setting of the needle valve I9. Thismotion is so slow, however, that the contacts 83 and 84 will not beseparated unless it continues for an appreciable length of time so thatthe passing of the torpedo beneath a quanunder it a suflicient length oftime for the contacts 83 and 84 to open thereby deenergizing thetorpedo.

The needle valves 19 and 52 are so adjusted that the time between theocculting of the photoelectric cells 68 and 69 and the detonation of thewar head will be suflicient to allow the torpedo to travel to thecentral portion of the ship, thereby exploding it in the mostadvantageous position.

Although only a few of the various forms in which this invention may beembodied have been shown herein, it is to be understood that theinvention is not limited to any specific construction, but might beembodied in various forms without departing from the spirit of theinvention or the scope of the appended claims.

Whatis claimed is:

1. In combination with a moving body, an explosive charge carriedthereby, means carried by said body for receiving light from a pluralityof directions external to said body and means operated by the change ofthe total intensity of said light for causing the detonation of saidexplosive charge.

2. In combination with a moving body, an explosive charge carriedthereby, a plurality of light receptivemeans mounted on said body forreceiving light from a corresponding plurality of directions and meansoperated by said light receptive means for detonating said explosivecharge when the total intensity of said illumination is changed.

3. Ina moving body, an explosive charge, means for detonating saidcharge, a plurality of light sensitive devices for operating saiddetonating means so that when the total illumination on said devices ischanged it will cause the detonation of said explosive charge and meansfor preventing the detonating of said explosive charge for apredetermined time after the launching of said body 4. In a moving body,an explosive charge, means for detonating said charge, a-plurality oflight sensitive devices for operating said detonating means so that at apredetermined interval after the intensity of the total illumination onsaid light sensitive devices is changed it will cause the detonation ofsaid explosive charge.

5. In a moving body, an explosive charge, means for detonating saidcharge, and two light sensitive devices set at corresponding angles fromthe vertical for operating said detonating means so that when the totalillumination on said devices is changed it will cause the detonation ofsaid explosive charge.

6. In a moving body, an explosive charge,

means for detonating said charge, and two light sensitive devices set at45 from the vertical for operating said detonating means so that whenthe total illumination on said devices is changed it will cause thedetonation of said explosive charge.

'7. In a moving body, an explosive charge, means for detonating saidcharge, a light sensitive device for operating said detonating means,and a plurality of lenses for focusing light on said device from acorresponding plurality of directions so that when the totalillumination from said plurality of directions on said device is changed11; wilbcause the detonation of said explosive charge.

8. In a moving body, an explosive charge, means for detonating saidcharge, a light sensitive device for operating said detonating means.and a pair of lenses for focusing light on said device from twodirections so that when the total illumination received from said twodirections on said device is changed it will cause the detonation ofsaid explosive charge.

9. In a moving body, an explosive charge, means for detonating saidcharge, and a light sensitive device for operating said detonatingmeans, and means responsive to variations in the total illuminationreceived from two directions at right angles to each other to cause saiddevice to detonate said explosive charge.

10. In a torpedo, an explosive charge, a pair of devices sensitive tolight from two different directions and means responsive to a change inthe total intensity of light received by said pair of devices todetonate said charge.

11. In a, torpedo, a; utility carried thereby, light sensitive meansalso carried by said torpedo, a plurality of devices for transmittingexternal light to said light sensitive means, said devices beingarranged to transmit light received from different directions wherebyvariations in light due to the rolling of the torpedo are compensatedfor, and means for operating said utility responsive to a variation inthe light received by said light sensitive means.

12. In a torpedo, a utility carried thereby, a pair of light sensitivedevices also carried by said torpedo, means for receiving light from aplurality of diflerent directions and for impressing -said light on saidlight sensitive devices, and

means for operating said utility responsive to a difference in theintensity of light received by said devices.

13. In a torpedo, a utility carried thereby, radiation sensitive meanscarried by said torpedo, a plurality of devices for transmittingexternal radiations to said means, said devices being arranged totransmit radiations received from different directions wherebyvariations in said radiations due to the motion of the torpedo itselfare compensated for and means for operating said 'utility responsive tovariation in the total amount of radiation received by both of said suchradiation sensitive means.

JOHN HAYS HAMMIOND, JR.

